天津大学傅平团队近日发现农田扩张减少了生物次生有机气溶胶和相关的辐射冷却。2025年6月24日出版的《自然—地球科学》杂志发表了这项成果。
耕地扩张是工业化以来全球土地利用最显著的变化。然而，对土地利用变化的辐射强迫的评估通常忽略了农田扩张对次生有机气溶胶的影响。研究组使用地球系统模型进行了一系列农田扩张敏感性实验，该模型结合了先进的二次有机气溶胶过程，包括有机新粒子的形成。我们的模型结果显示工业化以来，由于农田扩张，生物次生有机气溶胶负担减少约10% 。这减少了与二次有机气溶胶相关的辐射散射和云滴形成，导致146 ± 112 mW m−2的辐射冷却强迫下降，相当于工业化以来二氧化碳引起的辐射变暖强迫的8%。
辐射影响主要归因于常绿和落叶阔叶林向农田的过渡。由于生物排放强度和背景云凝结核浓度的变化，在未来气候变暖和人为气溶胶和前体气体排放减少的情况下，辐射影响预计将增加约50%。应对粮食安全和气候变化的政策应考虑到农田扩张产生的生物次生有机气溶胶的辐射影响。
附：英文原文
Title: Cropland expansion reduces biogenic secondary organic aerosol and associated radiative cooling
Author: Zhu, Jialei, Penner, Joyce E., Hong, Chaopeng, Liu, Hao, Zhao, Xi, Deng, Junjun, Liu, Cong-Qiang, Zhang, Qiang, Fu, Pingqing
Issue&Volume: 2025-06-24
Abstract: Cropland expansion has been the most notable change in global land use since industrialization. However, assessments of radiative forcing from land-use change have generally neglected the effects of cropland expansion on secondary organic aerosol. Here we perform a series of cropland expansion sensitivity experiments with an Earth system model that incorporates advanced secondary organic aerosol processes, including organic new particle formation. Our model results show an ~10% decrease in biogenic secondary organic aerosol burden due to cropland expansion since industrialization. This has reduced radiation scattering and cloud droplet formation associated with secondary organic aerosol, leading to a 146±112mWm2 decline in its radiative cooling forcing, equivalent to 8% of CO2-induced radiative warming forcing since industrialization. The radiative impact is mainly attributed to the transition from evergreen and deciduous broadleaf forests to croplands. The radiative impacts are projected to increase by approximately 50% under future climate warming and reduced anthropogenic aerosol and precursor gas emissions, due to changes in biogenic emission intensity and background cloud condensation nuclei concentration. Policies addressing food security and climate change should account for the radiative impact of biogenic secondary organic aerosol from cropland expansion.
DOI: 10.1038/s41561-025-01718-z
Source: https://www.nature.com/articles/s41561-025-01718-z